how to detect, disconnected network connection

[taraben . a]

Hello,

I have a simple tcp-server program derived from TCPSession.
My problem now is how to detect disconnected sessions.
1. disconnect by client, solved by messages from Wolfgang and Christian. 
 Return 0 bytes read.
2. disconnect by unplugging the network cable. HyperTerminal (my Client 
on Windows side) detects that the connection lost.

I already tried the bad() function and pendigError. But it seems 
everything normal.

btw. What I expect is a excpetion or pendingError.

My server program works under linux.

Many tanks for help,

Adib.